Detergents and dispersants are known to assist in maintaining reduced amounts of deposits on engine components. The lubricant industry has a number of engine tests used to evaluate lubricant's ability to handle deposits and sludge including the Sequence VG, Sequence IIIG, Volkswagen TDI, Caterpillar 1N, and Mercedes Benz OM501LA.
With recent changes to engine specifications there is an increasing demand on the lubricant to reduce deposits. For instance, the ILSAC GF-5 specification requires a 4.0 piston merit rating in the Sequence IIIG (vs. 3.5 for GF-4).
U.S. Pat. No. 3,933,662 (Lowe, published 20 Jan. 1976) discloses monoester polyalkoxylated compounds combined with alkaline earth metal carbonates dispersed in a hydrocarbon medium to provide lubricating compositions of superior acid neutralizing capability and rust inhibition in internal combustion engines. The internal combustion engine tested is a Sequence IIB engine. The Sequence IIB engine test evaluates valve guide rust and pitting.
U.S. Pat. No. 4,305,835 (Barber et al, published 15 Dec. 1981) discloses lubricating oil composition for use in the crankcase of an internal combustion engine, having improved resistance to the formation of emulsion-sludge in the area under the engine rocker cover, which contains the combination of an oxyalkylated alkylphenol-formaldehyde condensation product and an oxyalkylated trimethylolalkane.
U.S. Pat. No. 4,402,845 (Zoleski et al., published 6 Sep. 1983) discloses improved spreadability of marine diesel cylinder oils by the incorporation therein of a polyethylene glycol of the formula: R—CH2O—(CH2CH2O)nH wherein n ranges from 7 to 40 and R is an alkyl group containing from 11 to 15 carbon atoms.
U.S. Pat. No. 4,438,005 (Zoleski et al., published 20 Mar. 1984) discloses improved spreadability of marine diesel engine cylinder lubricants by the incorporation therein of a spreadability improving amount of at least one polyoxyethylene ester of the formula: wherein n ranges from 18 to 22 and R is an alkyl group having 11 to 17 carbon atoms in the chain.
U.S. Pat. No. 4,479,882 (Zoleski et al., published 30 Oct. 1984) discloses improved spreadability of marine diesel cylinder oils by the incorporation therein of a spreadability improving amount of a polyalkoxylated phenoxy compound having the formula: wherein R is an aliphatic hydrocarbyl group having from 5 to 70 carbon atoms and n ranges from 14 to 30.
U.S. Pat. No. 4,493,776 (Rhodes, published 15 Jan. 1985) discloses a lubricating composition with improved rust and corrosion inhibition comprising an additive that is a combination of (A) R1O[C2H4O]xH and/or R2O[C3H6O]yH with (B) R3O[C2H4O]x[C3H6O]yH and/or R4O[C3H6O]y[C2H4O]xH, wherein R1, R2, R3 and R4 are hydrocarbyl radicals selected from alkyl, aryl, alkaryl, and arylalkyl groups or combinations thereof having from about 10 to about 24 carbon atoms; and wherein x and y may vary independently in the range from 3 to about 15. The additives are hydroxyl-terminated.
U.S. Pat. No. 4,973,414 (Nerger et al., published 27 Nov. 1990) discloses monofunctional polyethers having hydroxyl groups contain, as built-in terminal groups or monomers, (a) 1 to 30% by weight of one or more C4- to C24-alkylmonophenols, (b) 1 to 30% by weight of one or more C8- to C24-monoalkanols, (c) 1 to 30% by weight of one or more C10- to C20-1,2-epoxyalkanes and (d) 45 to 80% by weight of propylene oxide or a lower alkylene oxide mixture consisting mainly of propylene oxide the sum of components (a) to (d) adding up to 100% by weight, and have average molecular weights of 600 to 2,500.
U.S. Pat. No. 5,397,486 (Small, published 14 Mar. 1995) discloses a method for inhibiting wear of silver wrist-pin bearings in a two-cycle railroad diesel engine which method comprises lubricating the internal portion thereof with a lubricating oil composition consisting essentially of: a single or multi-grade oil of lubricating viscosity; a sufficient amount of a calcium overbased sulfurized alkylphenate composition so that the total base number in the lubricating oil composition is from about 5 to about 30; and a wear-inhibiting amount of at least one lubricating oil soluble and compatible compound based upon a hydroxy-terminated polyalkylene oxide having 2 to 6 carbon atoms.
Polyalkoxylated compounds are also disclosed in U.S. Pat. No. 2,681,315 (Tongberg, published 15 Jun. 1954) and U.S. Pat. No. 2,833,717 (Whitacre, published 6 May, 1958) teaching lubricating oil compositions containing poly(oxyethylene)alkylphenols useful as rust or corrosion-inhibiting additives.
U.S. Pat. No. 2,921,027 (Brennan 12 Jan. 1960) teaches poly(oxyethylene)sorbitan fatty acid ester as a rust inhibitor.
1,2-poly(oxyalkylene)glycol lubricating compositions are disclosed in U.S. Pat. No. 2,620,302 (Harle, published 2 Dec. 1952), U.S. Pat. No. 2,620,304 (Stewart et al., published 2 Dec. 1952), and U.S. Pat. No. 2,620,305 (Stewart et al., published 2 Dec. 1952).